Thanks and sorry for the insufficient details.It is a PCI card. No. I haven't tried these cards as yet. I'd like to check before I buy the card as I now have a Realtek 8139D card which works fine with Win XP and I am now connected to the internet through this card.My connection is a broadband connection thru ADSL modem.If Ubuntu does not detect, then I am back to square one. That is why I'd like to confirm before buying the D-link 520 TX or the 538 TX, the only two available with my dealer.